Technical Field
The invention relates to a decoding method, and more particularly, to a decoding method of a rewritable non-volatile memory module, a memory storage device and a memory controlling circuit unit using the same.
Description of Related Art
The markets of digital cameras, cellular phones, and MP3 players have expanded rapidly in recent years, resulting in escalated demand for storage media by consumers. The characteristics of data non-volatility, low power consumption, and compact size make a rewritable non-volatile memory module (e.g., flash memory) ideal to be built in the portable multi-media devices as cited above.
Generally, data to be written to a rewritable non-volatile memory module may be encoded according to an error correcting codes (ECC). Data read from a rewritable non-volatile memory module may also be processed by a corresponding decoding procedure. However, the correcting ability of the ECC has limitation, and the error probability of data stored in the rewritable non-volatile memory module may change with the life of the rewritable non-volatile memory module. Generally, if the erasing count of a physical erasing unit in the rewritable non-volatile memory module increasing, then the error probability of the data may be increased correspondingly, and may causing that the error bit can not be corrected. Therefore, how to improve a correcting ability of decoding is one of the major subjects for person skilled in the art.
Nothing herein should be construed as an admission of knowledge in the prior art of any portion of the present invention. Furthermore, citation or identification of any document in this application is not an admission that such document is available as prior art to the present invention, or that any reference forms a part of the common general knowledge in the art.